Ok, so your husband informed you he felt the only way he could even consider recovery is to have a threesome where you pick out the woman and participate or he won't consider it and now he's confiding in an ex girlfriend. Sounds like he should be posting here as well.
That said, he'd have nothing to tell if you hadn't had an affair. You're upset he's spreading your business and consider it spiteful. I'm sure he views your choices as spiteful as well.
You've posted on this site about his actions and nothing about your choices. From your few posts doesn't sound like you've even started examination, just score keeping.
If he's abusive and inappropriate then perhaps not a great relationship to save. Regardless, your choices will need to be worked on in order to become healthy. I'd start there. You'll have to end up there anyway.
'til the roof comes off. 'til the lights go out. 'til my legs give out, can't shut my mouth